Centro de Investigación en Biotecnología Aplicada-Instituto Politécnico Nacional, Ex-Hacienda de San Juan Molino, Tepetitla de Lardizábal, Tlaxcala, México.
Facultad de Ciencias Naturales, Universidad Autónoma de Querétaro, Avenida de las Ciencias S/N Juriquilla, Querétaro, México.
PLoS One. 2019 Jan 4;14(1):e0209711. doi: 10.1371/journal.pone.0209711. eCollection 2019.
Dye-decolorizing peroxidase (DyP) from the white rot basidiomycete Pleurotus ostreatus is a heme peroxidase able to oxidize diverse substrates, including recalcitrant phenols and dyes. This study analyzed the effect of chemical dyes on P. ostreatus growth, DyP activity and the expression of four Pleos-dyp genes during the time-course of Pleurotus ostreatus cultures containing either Acetyl Yellow G (AYG), Remazol Brilliant Blue R (RBBR) or Acid Blue 129 (AB129) dyes. Additionally, Pleos DyP1 was heterologously expressed in the filamentous fungus Trichoderma atroviride in order to explore the potential of a secreted recombinant enzyme for decolorizing different dyes in cultures and plate assays. The addition of dyes had an induction effect on the enzymatic activity, with the fermentations undertaken using RBBR and AYG dyes presenting the highest total DyP activity. DyP gene expression profiles displayed up/down regulation during the culture of three Pleos-dyp genes (Pleos-dyp1, Pleos-dyp2 and Pleos-dyp4), while Pleos-dyp3 transcript was not detected under any of the culture conditions studied. A 14-fold relative induction level (log2) increase for Pleos-dyp2 and Pleos-dyp4 in AB129 and AYG, respectively, was also found. The presence of AB129 resulted in the highest Pleos-dyp1 gene induction and repression level, corresponding to 11.83 and -14.6-fold relative expression and repression levels, respectively. The lowest expression level of all genes was observed in RBBR, a response which is associated with the growth phase. The filamentous fungus Trichoderma atroviride was successfully transformed for the heterologous expression of Pleos-dyp1. The modified strains (TaDyP) were able to decolorize mono-azo, di-azo, anthraquinone and anthracenedione dyes with extracellular DyP1 activity found in the culture supernatant. After 96 h of culture, the recombinant TaDyP strains were able to degrade (decolorize) 77 and 34% of 0.05mM AB129 and 0.25mM AYG, respectively.
白腐真菌糙皮侧耳（Pleurotus ostreatus）中的染料脱色过氧化物酶（DyP）是一种血红素过氧化物酶，能够氧化包括难处理的酚类和染料在内的各种底物。本研究分析了化学染料对糙皮侧耳生长、DyP 活性以及四种 Pleos-dyp 基因表达的影响，这些基因在含有乙酰黄 G（AYG）、雷玛唑亮蓝 R（RBBR）或酸性蓝 129（AB129）染料的糙皮侧耳培养物中随时间的变化。此外，Pleos DyP1 在丝状真菌里氏木霉（Trichoderma atroviride）中进行了异源表达，以探索分泌的重组酶在培养物和平板测定中对不同染料进行脱色的潜力。染料的添加对酶活性有诱导作用，使用 RBBR 和 AYG 染料进行的发酵呈现出最高的总 DyP 活性。DyP 基因表达谱在三种 Pleos-dyp 基因（Pleos-dyp1、Pleos-dyp2 和 Pleos-dyp4）的培养过程中表现出上调/下调调控，而在任何研究的培养条件下均未检测到 Pleos-dyp3 转录本。在 AB129 和 AYG 中，Pleos-dyp2 和 Pleos-dyp4 的相对诱导水平（log2）分别增加了 14 倍和 14 倍。AB129 的存在导致 Pleos-dyp1 基因的诱导和抑制水平最高，相对表达和抑制水平分别为 11.83 倍和-14.6 倍。所有基因的表达水平最低是在 RBBR 中，这与生长阶段有关。丝状真菌里氏木霉成功地进行了异源表达 Pleos-dyp1 的转化。修饰的菌株（TaDyP）能够用细胞外 DyP1 活性在培养物上清液中对单偶氮、二偶氮、蒽醌和蒽二酮染料进行脱色。在 96 小时的培养后，重组 TaDyP 菌株能够分别降解（脱色）0.05mM AB129 和 0.25mM AYG 的 77%和 34%。
